1. Field of the Invention
The present invention relates to an absorbent composition including a hydrogel-forming polymeric material and a microfiber; disposable absorbent products, including the absorbent composition, intended for the absorption of body liquids; and a process for preparing the absorbent composition.
2. Description of the Related Art
The use of hydrogel-forming polymeric materials, commonly known as superabsorbents, in disposable absorbent personal care products is known. Such absorbent materials are generally employed in absorbent products such as diapers, training pants, adult incontinence products, and feminine care products in order to increase the absorbent capacity of such products while reducing their overall bulk. Such absorbent materials are generally present in absorbent products in a fibrous matrix, such as a matrix of wood pulp fluff. A matrix of wood pulp fluff generally has an absorbent capacity of about 6 grams of liquid per gram of fluff. The absorbent materials described above generally have an absorbent capacity of at least about 10, preferably of about 20, and often of up to 100 times their weight in water. Clearly, incorporation of such absorbent materials in personal care products can reduce the overall bulk while increasing the absorbent capacity of such products.
A wide variety of materials have been described for use as hydrogel-forming polymeric materials in such personal care products. Such materials include natural-based materials such as agar, pectin, gums, carboxyalkyl starch, and carboxyalkyl cellulose, as well as synthetic materials such as polyacrylates, polyacrylamides, and hydrolyzed polyacrylonitrile.
It is also known to combine a hydrogel-forming polymeric material with other materials by various methods in order to enhance the absorbent or other properties of the hydrogel-forming polymeric material. One method of preparing an absorbent composition, for example, comprises blending a hydrogel-forming polymeric material and fibers.
Unfortunately, many mechanical methods of treating or preparing an absorbent composition comprising a hydrogel-forming polymeric material result in the absorbent properties of the hydrogel-forming polymeric material being negatively affected. For example, many known hydrogel-forming polymeric materials are single particles or agglomerations of fine particles. When such materials are treated by mechanical methods such as blending, the particles or agglomerations are typically shattered or broken apart, which negatively affects the absorbent properties of the hydrogel-forming polymeric material.